This invention relates to pipes for smoking tobacco and other combustible materials. The invention pertains in part to a mouthpiece construction which is suitable to a wide variety of pipes, but the remaining features hereof are peculiar to devices referred to generally as waterpipes, wherein the smoke generated by the combustible material is passed upwardly in the form of bubbles through a body of water which cools and humidifies the smoke before it reaches the smoker.
Nubla U.S. Pat. No. 3,703,179 discloses a submerged filter in a waterpipe; and, McFadden et al U.S. Pat. No. 3,881,499 describe a system which utilizes two or four tubes which carry smoke into the lower liquid area of the cooling chamber of a waterpipe. The Nubla pipe would be incapable of breaking the smoke into small bubbles unless the filter is so fine that inhalation is extremely difficult. The McFadden et al device provides only one bubble-forming aperture for each smoke inlet pipe, therefore rendering it incapable of maximization of appropriate bubble-forming means.
One feature of the present invention is based upon the inventor's recognition that the cooling and humidification of smoke is dependent upon the total surface area of the smoke bubbles, and that this surface area for a given volume of smoke may be increased by reducing the size and increasing the number of bubbles. This is achieved by providing a given smoke inlet conduit with a bubble-forming means which has a plurality of spaced apart smoke-releasing apertures for breaking the smoke into a plurality of bubble-forming streams. These apertures may take various forms, including but not limited to slits and circular perforations disclosed in this application, such apertures preferably being separated by a distance greater than their dimension to prevent reunification of the small bubbles into larger bubbles.
In prior art pipes made and sold by the inventor, a deentrainment chamber has been provided immediately preceding the mouthpiece, the deentrainment chamber giving the froth formed by the smoke and water a residence time, permitting the smoke to be released from the water to avoid the inhalation of water through the mouthpiece. This is particularly important in pipes of small dimensions where the mouthpiece is close to the smoke cooling chamber. In prior devices, the deentrainment chamber has been of commensurate extent and gravitational potential as the upstream smoke cooling chamber, and a check valve was provided in an upper part of the deentrainment chamber.
The deentrainment chamber of the present invention is of an improved design which optimizes the utilization of volume within the pipe, this being achieved by providing a gravitational drain means with a drain opening located near the bottom of the deentrainment chamber, permitting the deetrainment chamber to discharge substantially all of its contents rather than constantly maintaining a substantial volume and depth of liquid therein.
A third feature of the present invention pertains to a mouthpiece design which is not essentially limited to use in connection with waterpieces. Previously, various types of holes, tubes and bits have served as the mouthpieces of pipes. To the knowledge of the present inventor, there have been no proposals simplifying the mouthpiece design to that it may be formed directly in a pipe housing which has plural intersecting walls.
According to the preferred embodiment of the invention, a pipe is provided with a smoke receiving chamber formed of a plurality of intersecting walls, and a mouthpiece opening is formed in at least two of the walls at their intersection, enabling a smoker's lips to be placed respectively against the two walls to surround the mouthpiece opening. This avoids undesirable protrusions from the pipe housing and affords a natural and comfortable means for drawing smoke from a pipe housing.
The previously-mentioned features of the invention are applicable to single stage pipes or multiple stage pipes.
Another feature of the present invention relates to multiple-stage waterpipes wherein the smoke is passed serially through a series of cooling stages, each of which is provided with a body of water through which smoke bubbles ascend for cooling and humidification. Multiple-stage pipes have been known, an early version thereof being shown by the Abizaid U.S. Pat. No. 848,424. If one had desired to increase the number of smoke cooling stages in such devices, it would have been necessary to remanufacture them by adding and assembling additional vessels, tubes and stoppers.
According to the present invention, a waterpipe may be formed of a plurality of interconnectible units or modules, constructed so that additional modules may be added therebetween to increase the number of smoke cooling stages. The insertable modules each would comprise a hollow body having at its opposite ends an inlet end and an outlet end, the hollow body including a vessel provided with a lower liquid space and an upper air space. An upwardly-extending passage in the module communicates from a point below the air space to a point at the elevation of the air space, and a downwardly extending passage leads into the lower liquid space from a point above the liquid space. Joint means are provided for connecting the inlet end of the hollow body to another module, and joint means are also provided for connecting the outlet end of the hollow body to another module. Preferably, a plurality of the modules are arranged in vertical succession, but horizontal arrangements are also suitable according to the invention. In an assembly of the modules, it is preferred to provide the modules with joints which are identical at their respective inlet ends and are identical at their respective outlet ends, thereby facilitating the insertion of additional modules into the system.